As the grandson of oceanographic explorer Jacques Cousteau and son of aquatic filmmaker Jean-Michel Cousteau, Fabien Cousteau has a large legacy to uphold. Now, just in time for World Oceans Day, the younger Cousteau is preparing to make his mark with Plant a Fish, a nonprofit focusing on worldwide ocean restoration. But before exploring the outer reaches of the planet’s seas, Plant a Fish will work in Cousteau’s home base: New York City.

Plant a Fish’s first project, launched Monday, saw Cousteau working with students at the Urban Assembly New York Harbor School, a Bushwick, Brooklyn public school. Cousteau led the students on a dive in Bay Ridge, Brooklyn to plant 130,000 oysters. “This used to be the world’s largest oyster rookery,” Cousteau tells Fast Company. He hopes that the program will eventually plant 1 billion oysters in the area.

Brooklyn is just the beginning for Plant a Fish. Cousteau also has visions of planting mangroves, coral reefs, and turtles in locations including the Florida Keys, the Maldives, and El Salvador. None of the projects are particularly cheap–it costs $5,000 to plant 10,000 oysters, for example, and $10,000 to plant a sea garden of mangroves. But Cousteau has faith that people will donate cash–or just their time. “This is grassroots,” he says.